Listen to Prince’s piano demo of “17 Days”

Piano & A Microphone: 1983 is due out in September

On Thursday, a demo version of Prince's "When Doves Cry" B-side track "17 Days" surfaced online courtesy of the late singer's estate, Pitchfork points out. The piano-laden rendition comes from a live rehearsal of the track, and features Prince singing and candidly giving off-the-cuff directions to stage directors.